Lift truck attachments



May 21, 1963 H. THIELE 3,090,494

LIFT TRUCK ATTACHMENTS Filed July 22, 1960 2 Sheets-Sheet 1 IN VEN TOR:

HANS THI LE BY Mytfi/ May 21, 1963 H. THIELE 3,090,494

LIFT TRUCK ATTACHMENTS Filed July 22, 1960 2 Sheets-Sheet 2 INVENTQR HANS THJELE BY v ATT'YS atent ifice Patented May 21, 1963 3,090, 34 LIFT TRUCK ATTACHMENTS Hans Thiele, Kassel-Auefeld, Germany, assignor to Spinrh faser Aktiengesellschaft, Kassel-Bettenhausen, Germany Filed Jrriy 22, 1960, Ser. No. 44,593 Claims priority, application Germany July 29, 1959 8 Claims. (Cl. 212-43) Thi operation relates to improvements which considerably enlarge the range of use of mobile lift trucks. Mobile lift trucks, with their vertically movable lifts, are used in many industrial plants to pick up, transport, and set down loads of various kinds. Their range of operation in loading and unloading can be extended somewhat by means for shifting or swinging the load boom, by tipping the truck chassis or by means for horizontal movement of the entire lifting mechanism. The extent of the range of operation, however, is always dependent on the stability of the lift truck so that it does not tip over by unbalance due to an overextended load. The load on the truck can only be picked up or deposited within the range of movement of the lift with the further proviso that the Weight of the load does not cause the truck to tip.

The basic objective of this invention is the enlargement of the range of operation in lift trucks. This objective is accomplished by utilizing a load bearing member and associated lifting means on said beam in connection with the lift or lifts of one or two mobile lift trucks. The load-bearing member has two spaced supports, at least one of which is the lift of a lift truck. In this combination, the load weight, though situated outside the normal range for the torque arm of the load on the lift truck has, in effect, a torque arm relative to the lift truck within the range wherein the lift truck does not tip under the load.

According to the invention, the lift truck is pivotally connected to a load-bearing member supported at its opposite end on a fixed or movable support. The position and/ or length of the loadbearing member can be changed to facilitate loading or unloading.

The pivotal connection of the lift and the load bearing member is at a position within the range wherein the load applied on the pivotal connection through the load-bearing member does not tip the truck.

This position is normally at or less than the maximum torque arm for the anticipated maximum capacity load for the lift truck operated without the auxiliary load bearing beam or member, above-described. For example, in a lift truck whose lift has a boom with a hook at the outer end, the load-bearing member is pivotally connected to the boom of the lift. The lift truck can thereby elevate the pivotally connected end of the loading bearing member to the desired height.

An especially favored combination is the load-bearing member supported at spaced points by two lift trucks. In this case, the second lift truck also is a readily-movable support for the intermediate load-bearing member. It is borne on a member of the lifts, e.g., the booms of two lift trucks. In this arrangement, the Ioadbearing member is connected to each lift by a ball-and-socket joint. The mobility of the combination makes this combination versatile in many loading and unloading situations.

The desired or required length of the load-bearing member will vary under different loading or unloading situations. Interchangeable load-bearing members of different lengths can be used. A preferred arrangement, however, consists of a load-bearing member which is adjustable in length; e.g., a telescopic loadbearing member whose length is automatically adjustable in correspondence to the relative positions of the two lift trucks upon which it is supported. In this embodiment of the invention, the entire unit of the two lift trucks supporting the load-bearing member can be moved about before, during or after the performance of the assigned tasks.

In a special development of the invention, the intermediate load-bearing member has a load lifting mechanism which is movable back and forth on said member. It frequently happens that it is impossible to drive a lift truck near enough up to the load to be moved, in order to grip said load with its boom and lift it. Where overhead cranes or trolleys cannot be used, e.g., because pipe lines are present, complicated lifting units may have to be set up and later again removed. For such situations, the present invention provides both cost-savings and timesavings.

In one type of construction, the load-bearing member can be a girder or pipe which is supported by the lift truck at one end and its other end on a non-mobile support at the requisite height. This support may be a V- shaped support to which the load-bearing member is attached, either rigidly or by a pivotable joint. In the lifting of a remotely situated load, its effective force is disposed of within the permissible torque arm range of the lift truck. The raised load on the load-bearing member is slid toward the lift truck and is taken over directly by the lift truck. If the load-bearing member is arranged between the booms of two lift trucks, the lifting and conveyance of such unfavorably situated loads situated outside the range of each individual truck i accomplished in a still simpler fashion. After lifting and sliding the load onto one boom, the load is carried by this truck, while the other truck directly takes over the transport of the loud-bearing member as soon as it is detached from the first truck. It is possible, in order to get around obstacles, such as pipes or bulky machinery parts, that movements of the stacker combination will be necessary before the load is taken over by one stacker. These movements are made possible with telescopic load-bearing member.

When the circumstances make it necessary, the booms of the lift trucks and loading bearing member can be locked with respect to each other so that the combination forms a substantially rigid frame. Further, for increas ing of the stability of the lift trucks and also for increasing the power which can be applied to release clamped or stuck loads, hydraulically-operated supports can be provided on the lift trucks to broaden their effective bases.

The present invention is described further with the aid of the drawings of particular embodiments of the invention.

FIG. 1 is a perspective view of load-lifting equipment on a load-bearing member connected to two lift trucks;

FIG. 2 is a side view of the load-lifting mechanism mounted on the load-bearing member designated by the circled numeral 2 in FIG. 1;

FIG. 3 is an end view, partly in cross-section, of the mechanism of FIG. 2;

FIG. 4 is a side elevation, partly in cross-section, of the universal joint designated by the circled numeral 4 in the embodiment of FIG. I; and

FIGS. 5 and 6 are a perspective view and a top plan view, respectively, of another embodiment of the invention.

The embodiment illustrated in FIGS 1-4 utilizes two lift trucks 10, each having a pair of parallel lift arms 11. Booms on the lift trucks are composed of a pair of bifurcated arms 12 which are mounted on the arms 11. These lift booms are raised and lowered on the arms 11 by conventional hydraulic or mechanical mechanism, which is not illustrated in detail. At the juncture of the bifurcated arms 12 there is a tubular, forwardly-extending segment of the boom on each mobile lift truck. The lift need not, necessarily, be a boom, but may be any structure suitably adapted for attachment to the load-bearing member.

The tubular segments 13 are connected by ball-andsocket joints 14 and 15 to a tubular load-bearing member 16 which consists of telescoped tubular sections 17 and 18. The telescopic tubular load-bearing member is easily adjustable in length to accommodate various loading and unloading situations requiring different lengths of the load-bearing member.

A load-lifting mechanism 19 is movably supported on the load-bearing member 16. The load-lifting mechanism may be of any conventional construction. Loadlifting mechanism 19 in the embodiment illustrated comprises a power driven chain hoist having a motor 20 and pulley arrangement 21. A load grasping hook 22 is attached to the end of the chain 23 of the power driven hoist.

The power driven hoist has its base mounted rigidly on a plate 23'. On the opposite side of the plate is attached a pair of right angle support arms 24 and 25. Journal pins 26 and 27 are mounted in the sides of the support arms, upon which journal pins wheels 28, 29, 30 and 31 are mounted. These wheels ride upon the upper and lower surfaces of the tubular load-bearing member 16 so that the load-lifting mechanism 19 can be moved as desired.

The arms 24 and are preferably secured to the plate 23 by journal pins 32 and 33 so that the arms 24 and 25 are pivotable relative to each other on the plate 23. In this arrangement, the load-lifting unit may be run between the tubular load-bearing member 16 and one of the tubular segments 13 of the booms of the lift trucks 10 when they are angularly disposed with relation to each other. This type of mounting gives the combination greater versatility in handling various loading situations by permitting the angular disposition of the booms of the trucks with relation to the load-bearing member 16. If desired, hydraulically-operated, retractable stabilizers 34 may be mounted on the fronts of the lift trucks so that the trucks have added stability when the stabilizers are lowered in contact with the floor during loading and unloading.

Ball-and-socket joints 14 and 15 are the most advantageous type of joints providing greatest versatility in various positions of the lift trucks 10 with relation to the load-bearing member 16. A connection permitting pivoting of the member 16 with relation to the booms 13 in the vertical plane is essential so that the booms of the lift trucks 10 can be raised and lowered in accordance with the loading or unloading requirements in positioning the hook 22. A connection allowing for pivotal movement of the booms 13 with relation to the tubular load-bearing member 16 is desirable because it permits the lift trucks to take various positions relative to the load-bearing member 16. A ball-and-socket joint satisfies both requirements.

The ball-and-socket joint may be of any conventional construction. The ball-and-socket joint 14 is illustrated in greater detail in FIG. 4. The ball-and-socket joint 15 may be of like construction. The tubular segment 13 of the boom of the lift truck has tightly secured in its hollow end a cylindrical base 35, on the protruding end of which is a ball 36. The section 18 of the load-bearing member 16 has a cylindrical member 37 tightly secured in its open end. The protruding end of the member 37 has external threads which are threaded into the socket 38 of the ball-and-socket joint. The end of the member 37 is tightly seated against the ball 36 and forms with the socket 38 and ball 36 the ball-and-socket joint. The purpose of the threaded connection is to permit the quick disassembly of the tubular load-bearing member 16 on the booms of lift trucks 10. A set screw may be used to lock the threaded connection. Furthermore, pins 39 may be used to secure the members 35 and 37 on the ends of the tubular members 13 and 18, respectively.

The embodiment illutrated in FIGS. 5 and 6 is one utilizing only one lift truck 40 which supports one end of the load-bearing member. The other end of the member is supported on a structural member. The lift truck 40 is similar in construction to the lift truck 10. It has lift arms 41 and a pair of bifurcated arms 42 forming a part of the elevatable boom. In this embodiment, however, the end segment of the boom is an I beam girder 43 of like construction with the I beam girder 44 which onstitutcs a load-bearing member. One end of the I beam 44 is mounted on a support 45 which is adjustable in height. The support 45 is an inverted V having tubular legs 46 and 47 in which are siidably mounted tubular extensions 48 and 49, respectively. The extensions 48 and 49 provide for the height adjustment of the support 45 and are held in the desired position by bolts 50 extending through holes in the legs 46 or 47 and extensions 48 or 49. Support feet 51 and 52 are hingedly connected to the end connections 48 and 49, respectively.

The load-lifting mechanism 53 consists of a pair of plates 54 and 55 mounted on opposite sides of the I beam 44. These plates support the power driven hoist mechanism 56 which raises and lowers chain 57 and its hook 58. The load-lifting mechanism 53 is supported on four wheels 63 which ride upon the upper surface of the lower section of the I beam. Each wheel is supported upon a stub axle 59 extending through the plates 54 and 55.

The I beam segment 43 of the boom of the lift truck 40 and the I beam loadbearing member 44 are connected by a hinge joint 61 which is pivotable in a vertical plane. This hinge connection 61 allows the boom to be raised and lowered while it is connected with the loadbearing member 44. With this type of binge, the I beam segment 43 is always in substantial alignment with the I beam load-bearing member 44. If it is desired to permit the boom 43 to be angularly positioned with relai tion to the load-bearing I beam 44 in the horizontal plane,

this can be done by providing a second hinge at right angles to the hinge 61giving a universal joint.

The I beam 44 can be rigidly attached to the support 45 or it can be attached by a removable pin connection 60. Further, the pin connection at may be rigid or may permit swinging of the I beam 44 relative to the support 45 in the horizontal plane, as desired. A retractable stabilizcr 62 similar in construction to the stabilizer 34, may be utilized on the lift truck 40 to provide additional stability in loading and unloading. The support 45 may be replaced by a lift truck in the embodiment of FIGS. 5 and 6 in a manner similar to the embodiment of FIGS. i4 in which case the lift truck may be connected to the load-bcaring member by a ball-andsocket joint or by hinge pivotable only in the vertical plane.

The foregoing embodiments of the invention are merely exemplary of the many possible types of construction which can be used to realize the generic concepts of this invention. This invention has many advantages and can be utilized in a wide variety of situations where loading and unloading situations prevent or inhibit the utilization of lift trucks, per se. In many cases, fixed installations of overhead cranes and the like can be dispensed with in favor of the combinations of this invention. When lift trucks are available in a given plant, the invention also provides a considerable saving in costs besides the facilitation of operations and versatile possibilities of utilization for the lift trucks.

The invention is hereby claimed as follows:

1. Load transferring apparatus comprising a mobile, industrial lift truck with a lift on the front of said truck, means for raising and lowering said lift, a load bearing member, a hinge pivotable in the vertical direction connecting said load-bearing member to said lift, means on said load-bearing member spaced from said hinge for additionally supporting said load'bearing member, and means on said loadbearing member for holding a load.

2. The combination of claim 1 wherein said hinge is a ball-and-socket joint.

3. The combination of claim 1 wherein the last-mentioned means is mounted to travel along said load-bearing member.

4. Load transferring apparatus comprising two mobile, industrial lift trucks with a lift on the front of each truck, means on each truck for raising and lowering its respective lift, a load-bearing member extending between the lifts of said trucks, a ball-and-socket joint at each end of said load-bearing member connecting said member to said lifts on said two mobile, industrial lift trucks, and means on said load-bearing member for holding a load.

5. The combination of claim 4 wherein the last-mentioned means is mounted to travel along said load-bearing member.

6. Load transferring apparatus comprising two mobile, industrial lift trucks with a lift on the front of each truck, means on each truck for raising and lowering its respective lift, a load-bearing member extending between the lifts of said trucks, said load-bearing member comprising telescoping sections whereby said load-bearing member 2 can be lengthened or shortened, a ball-and-socket joint at each end of said load-bearing member connecting said member to said lifts on said two mobile, industrial lift trucks, and means on said load-bearing member for holding a load.

7. Load transferring apparatus comprising two mobile, industrial lift trucks with a lift on the front of each truck, means on each truck for raising and lowering its respective lift, a load-bearing member extending between said lifts, a ball-and-socket joint at each end of said load-bean ing member connecting said member to a boom on each of said lifts, means for holding a load, and wheel means supporting said last-mentioned means on said load-bearing member whereby said last-mentioned means can be moved along said load-bearing member as well as onto or off of either of said booms.

8. A load transferring apparatus as claimed in claim 7 wherein said means for holding a load is a chain hoist.

References Cited in the file of this patent UNITED STATES PATENTS 2,239,558 Hammar Apr. 22, 1941 2,516,364 Caddell -a July 25, 1950 FOREIGN PATENTS 619,042 Great Britain Mar. 3, I949 

1. LOAD TRANSFERRING APPARATUS COMPRISING A MOBILE, INDUSTRIAL LIFT TRUCK WITH A LIFT ON THE FRONT OF SAID TRUCK, MEANS FOR RAISING AND LOWERING SAID LIFT, A LOAD-BEARING MEMBER, A HINGE PIVOTABLE IN THE VERTICAL DIRECTION CONNECTING SAIDLOAD-BEARING MEMBER TO SAID LIFT, MEANS ON SAID LOAD-BEARING MEMBER SPACED FROM SAID HINGE FOR ADDITIONALLY SUPPORTING SAID LOAD-BEARING MEMBER, AND MEANS ON SAID LOAD-BEARING MEMBER FOR HOLDING A LOAD. 